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Rocky
12-29-2006, 11:12 AM
NOTE: Take into account that not all engine noises are abnormal and may be actually considered normal by the manufacturer please check before making asumptions!

Right this is a guide that will guide you with engines noises and what the possible causes maybe! Also make a note of the condition the motor is in when reproducing the noise!

TOP END NOISES

Ticking ---> Low to high RPM's hot or cold ---> Valve adujustment, bent valve/ valve seat. Excess valve stem to valve guide clearence

Ticking ---> Low to high RPM's hot ---> excess pad to lifter clearence, Lifter shape, lifter-to-cylinder head clearencem worn camshaft lobes/rocker arms

Ticking/Clatter ---> Idle to mid-range, hot or cold ---> loose cam chain

Clatter ---> Primarily at idle, hot ---> Camshaft end play

Knocking ---> Idle to mid-range, hot or cold ---> Camshaft end play thrust clearence. Loose cam sprocket bolts

Rattle/slapping ---> Idle to low speed, Primarily hot ---> excessive piston-to-cylinder clearence

Rattle/Pinging ---> Mid to high range, under load, hot --> Detonation


Bottom End Noises

Knocking ---> Idle to mid-range or specific RPM, hot or cold --> loose exhaust system or broken internally

---> Accelerating, decel, hot or cold ---> Loose primary chain, primary drive gear nut

---> Primarily at idle, hot or cold ---> Crankshaft end play

---> Idle to mid-range, primarily hot ---> Improper rod bearing

---> Idle to mid-range, under load, hot ---> excess main bearing clearance

Rattling ---> Idle to mid-range, hot or cold loose cam chain

Chattering ---> Low to mid-range shifting under load ---> worn friction plates or clutch housing

Whirring ---> All speeds, Primarliy hot ---> worn main bearings

Tick or Clunk ---> Low to high RPM's, one or more gears, hot or cold ---> Transmission

Howling,grinding,squealing ---> low to high RPM's under load, all gears, clutch in or out, hot or cold ---> Improper tooth contact, Improper backlash in primary, middle or final drive gear!

Remember! the conditions stated here will not always apply to your bike but might always be the same problems, and the problems stated are only POSSIBLE CAUSES not actual problems, also when listening to your motor be very carful becuase the noise you hare from one part of the motor may actually be comming from a completely different area! its best to use a pair of engine stethoscopes from harbour freight or if your too ghetto just use a hefty sized wrench to carry the engine vibrations well

Save-the-Manatee
12-29-2006, 02:39 PM
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